1. Field of the Invention
The present invention relates to an assembly, e.g., for sealing components of a valve.
2. Description of the Related Art
A known assembly for sealing a force transmission element (which is described in published German patent application document DE 10 2009 047 009 A1) guided in a duct in a body is used in a fuel injector in fuel injection systems for internal combustion engines for sealing components of the valve, that are not resistant to fuel, such as the piezoelectric actuator for the valve control, from the fuel present in a valve chamber of the valve under system pressure. The valve chamber is bordered by a valve housing and a valve body that is fixed to the valve housing in a sealed manner. The valve body has a duct for a valve needle, which extends from a valve opening arranged in front of the valve chamber up to the actuator. In the area of the duct, the valve needle carries a slide ring, fixed on it, which borders a narrow radial gap with the valve body within the duct. In order to prevent the passage of the fuel through this radial gap, the end face of the valve body bordering the valve chamber is covered by an annular diaphragm, which with its inner edge is fixed on the slide ring and its outer edge on the valve body. The region on the valve body covered by the diaphragm is filled with a medium.
The medium has a yield stress which is selected as a function of the fuel pressure prevailing in the valve chamber, for example, a soft mass having a high yield stress, such as a Bingham fluid, viscous silicone oil or transformer oil. In order to fill the covering region of the diaphragm with the medium, a chamber is present in the valve body, which subdivides the valve body into a front and a rear body part. In the front body part, a connection to the covering region is produced and in the rear body part, using the slide ring, the sliding guide of the valve needle in the valve body is implemented. The filling of the chamber with the medium takes place via a filling hole inserted into the valve needle, which opens out into the chamber. After the filling in of the medium, the filling hole is closed by pressing in a ball.